I like asking, not assuming, just in case my partner has a great idea, and one which I would love to see realized, so often times, even if something is left open, like the case in point, I like to see if there is any particular idea behind it. Not only to see what my partner intended, if anything, but also so I can get a feel for them better. In this case, you intended it as Chall's magic, and followed that with a list of ideas. Being able to read the ideas better allows me to reply in a way that will avoid conflicting with my partner, and make for a more fun and entertaining RP :P
I too have had an RP ripped in a direction I did not see coming, however more often than not, when it comes across entirely unexpected, it has almost always been to the detriment of my and my partner's enjoyment. Then again, I am stubborn in some things that my partner does not know of until they rub it the wrong way, and quite often with many partners I have upset them by trying to put and RP back into some semblance of order after a rather rude upset. I do not accuse you of these things, you should know, however I hope you do not mind me asking, often, of some motivations you may have for one thing or another.
It is good to know how open you are on these things, and from now on I will try and relax a bit. Oh, I have not mentioned it before, but I am a stanch believer in fully sharing all NPCs, no matter who came up with them originally. This does not mean I disagree with raising an objection should I use and NPC you created in a way you do not see them acting. I believe coming up with personalities and patterns for reoccurring NPCs is a good thing and allows for free use between player. I only bring this up because you called the spirit. . ."an NPC to some extent." I need to know if this means you would not like me to use him/her(May look like Wren, but I do not assume gender based on what form a spirit decides to take least it be stated at their own form).